Implantable auditory stimulation system and method with offset implanted microphones

ABSTRACT

An improved implantable auditory stimulation system includes two or more implanted microphones for transcutaneous detection of acoustic signals. Each of the implanted microphones provides an output signal. The microphone output signals may be combinatively utilized by an implanted processor to generate a signal for driving an implanted auditory stimulation device. The implanted microphones may be located at offset subcutaneous locations and/or may be provided with different design sensitivities, wherein combinative processing of the microphone output signals may yield an improved drive signal. In one embodiment, the microphone signal may be processed for beamforming and/or directionality purposes.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 61/182,627, filed May 29, 2009, entitled “IMPLANTABLE AUDITORYSTIMULATION SYSTEM AND METHOD WITH OFFSET IMPLANTED MICROPHONES”, theentirety of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to implantable auditory stimulationsystems, and more particularly, to an improved system and method thatemploys output signals from a plurality of implantable microphones togenerate a stimulation drive signal.

BACKGROUND OF THE INVENTION

The utilization of implanted hearing instruments continues to increase.In this regard, implantable hearing devices provide operative andcosmetic advantages relative to conventional ear canal hearing devices.For example, implantable hearing devices offer operative advantages inrelation to patient's having certain types of conductive orsensorineural hearing loss (e.g. mixed hearing loss comprising aconductive loss component of 45 dB or more with sensorineural hearingloss component of 40 dB or more). These patients are generally known toperform poorly with conventional hearing aids because their conductiveand sensorineural hearing loss components are additive and thesepatients require substantial amounts of gain and output for properspeech recognition.

Typically, an implanted hearing instrument may comprise implantedcomponentry for stimulating a middle ear component of a patient'sauditory system, or alternatively, for electrically stimulating acomponent of a patient's auditory system. In the former regard, one typeof middle ear stimulation device includes an electromechanicaltransducer having a magnetic coil that drives a supported vibratoryactuator positioned to contact and mechanically stimulate the ossicularchain of a patient. In another approach, a magnet is attached to theossicular chain of a patient and a spaced coil is energized to generatea fluctuating magnetic field to induce magnet movement at acousticfrequencies.

In relation to electrical stimulation approaches, or auditoryneurostimulation, known devices include auditory brain stem implant(ABI) devices and cochlear implant (CI) devices. In the case of CIdevices an electrode array is inserted into the cochlea of a patient,e.g. typically into the scala tympani so as to access and follow thespiral currature of the cochlea. The array electrodes are selectivelydriven to stimulate the patient's auditory nerve endings to generatesound sensation. In this regard, a CI electrode array works by utilizingthe tonotopic organization, or frequency-to-location mapping, of thebasilar membrane of the inner ear. In a normal ear, sound vibrations inthe air are transduced to physical vibrations of the basilar membraneinside the cochlea. High frequency sounds do not travel very far alongthe membrane, while lower frequency sounds pass further along. Themovement of hair cells, located along the basilar membrane, creates anelectrical disturbance, or potential, that can be picked up by auditorynerve endings that generate electrical action pulses that travel alongthe auditory nerve to the brainstem. In turn, the brain is able tointerpret the nerve activity to determine which area of the basilarmembrane is resonating, and therefore what sound frequency is beingsensed. By directing which electrodes of a Cl electrode array areactivated, cochlear implants can selectively stimulate different partsof the cochlea arid thereby convey different acoustic frequenciescorresponding with a given audio input signal.

With ABI systems a plurality of electrodes may be implanted at alocation that bypasses the cochlea. More particularly, an array ofelectrodes may be implanted at the cochlea nucleus, or auditory cortex,at the base of the brain to directly stimulate the brainstem of apatient. Again, the electrode array may be driven in relation to thetonotopic organization of a recipient's auditory cortex to obtain thedesired sound sensation.

As may be appreciated, in the case of either middle ear stimulationdevices or neurostimulation devices, audio signals from a microphone maybe processed, typically utilizing what is referred to as a speechprocessor, to generate signals to drive the stimulation device. In thisregard, as implanted hearing instruments have continued to evolve, theutilization of implanted microphones has increased. However, theemployment of implanted microphones has presented a number of challengesin relation to realizing a desired signal-to-noise ratio with adequatesensitivity across a normal hearing range of acoustic frequencies.

SUMMARY OF THE INVENTION

The present invention is directed to an improved implantable auditorystimulation system and method that contemplates the utilization of aplurality of implanted microphones to provide a corresponding pluralityof output signals which may be combinatively employed in the generationof a signal to drive an implantable auditory stimulation device. In thisregard, the present inventors have recognized the advantage of utilizingmultiple microphones that may be located at differing subcutaneouslocations having differing acoustic and vibrational characteristics. Thepresent inventors have also recognized the benefit of utilizing aplurality of microphones that may be located at offset subcutaneouslocations to facilitate the utilization of the multiple microphoneoutput signals for beamforming and directionality purposes.Additionally, the present inventors have recognized the advantage ofemploying multiple implanted microphones having different designsensitivities.

An improved implantable auditory stimulation system may comprise aplurality of implantable microphones, including at least a firstmicrophone operative to transcutaneously receive acoustic signals andgenerate a first microphone output signal in response thereto, and asecond microphone operative to transcutaneously receive acoustic outputsignals and generate a second microphone output signal in responsethereto. The system may further include a processor (e.g. a speechprocessor), operatively interconnected to the first microphone and tothe second microphone, adapted to combinatively use the first and secondmicrophone output signals to generate a drive signal. In turn, thesystem may employ an implantable auditory stimulation device,operatively interconnected to the processor, to stimulate an auditorysystem component of a patient in response to the drive signal.

In one aspect, at least a first microphone may be disposed within animplantable first housing and at least a second microphone may bedisposed within an implantable second housing, wherein the first andsecond housings are structurally separate, e.g., not fixedlyinterconnected. In this regard, the first and second implantablehousings may be separately positioned at spaced subcutaneous locations.By way of example, in one arrangement the first housing may be disposedon a patient's skull (e.g. on the temporal bone posterior to theexternal auditory canal), while the second microphone may be disposed onsoft tissue of the patient (e.g. near the sterno-cleido-mastoid muscle).In the later regard, soft tissue placement may be provided as taught byU.S. Pat. No. 7,354,394, hereby incorporated by reference in itsentirety.

In another aspect, a first microphone may be disposed within animplantable housing and a second microphone may be disposed within thesame implantable housing but separated in distance across the housing.In this device, the position of the first and second microphones withinthe housing may be chosen for optimal placement relative to a patient'sphysiological features in relation to contemplated processing of themicrophone output signals. For example, the position of the firstmicrophone may be chosen for optimal placement near the externalauditory canal, whereas the position of the second microphone may bechosen for optimal placement near the temporalis muscle. The microphoneoutput signals may then be combinatively employed.

It should be appreciated that numerous combinations of two or moreimplantable microphones can be envisioned in which the microphones aregrouped in either the same or separate housings to achieve specificacoustic amplification and signal processing purposes. In this regard,it should also be appreciated that various combinations of implantablemicrophones may be employed in which more than two microphones areemployed in the same or multiple housings.

In a further aspect, a plurality of implantable microphones may bedisposed at offset implant locations, wherein a corresponding pluralityof microphone output signals may be combinatively employed by aprocessing module of processor for beamforming and/or directionalitypurposes. In this regard, the plurality of microphones may be located inthe same or separate implant housings.

In another aspect, at least a first microphone may be provided to have afirst predetermined minimum sensitivity across a first predeterminedfrequency range, and at least a second microphone may be provided tohave a second predetermined minimum sensitivity across a secondfrequency range, wherein the first and second predetermined frequencyranges are at least partially non-overlapping. In this regard, thesensitivities of the first and second microphones may be advantageouslyprovided in corresponding relation to the acoustic and vibrationalcharacteristic of the intended implant locations. Further, one or moreadditional microphones may be provided having correspondingpredetermined minimum sensitivities across corresponding predeterminedfrequency ranges that may the same or at least partially non-overlappingwith the first and second predetermined frequency ranges.

In one implementation, a first microphone may be provided forpositioning on a patient's skull (e.g. posterior to the externalauditory canal) with an implanted design sensitivity of at leastapproximately −60 to −50 dB V/0.1 Pa across a frequency range of about50 H_(z)to 3000 H_(z). In the same or another implementation a secondmicrophone may be provided for positioning on soft tissue of a patient(e.g. near the sterno-cleido-mastoid muscle) with an implanted designsensitivity of at least about approximately −60 to −50 dB V/0.1 Paacross a frequency range of about 1500 H_(z) to 10000 Hz. Variousfiltering techniques can be employed to achieve roll-off above and belowthe band of interest.

In a further aspect, at least one of a first implantable microphone anda second implantable microphone may be operatively interconnected to theprocessor via at least a flexible first communication cable, therebyfacilitating selective placement of the microphones at offsetsubcutaneous locations. In one approach, the first communication cablemay have a first end that is one of fixedly interconnected to, andselectively interconnectable to and disconnectable from the processor.

In another approach, the first communication cable may have a first endthat is one of fixedly interconnected to, and selectivelyinterconnectable to and disconnectable from, an implantable connector,and a second end that is one of fixedly interconnected to, andselectively interconnectable to and disconnectable from one of the firstmicrophone and second microphone. In turn, a flexible secondcommunication cable may be utilized to operatively interconnect theconnector to the processor. In this regard, the second communicationcable may have a first end that is one of fixedly interconnected to, andselectively interconnectable to and disconnectable from, the processor,and a second end that is one of fixedly interconnected to, andselectively interconnectable to and disconnectable from, the implantableconnector.

In the later regard, a flexible third communication cable may beprovided having a first end that is one of fixedly interconnected to,and selectively interconnectable to and disconnectable from the auditorystimulation device, and a second end that is one of fixedlyinterconnected to, and selectively interconnectable to anddisconnectable from the implantable connector. In another approach, thesecond end of the third communication cable may be one of fixedlyinterconnected to, and selectively interconnectable to anddisconnectable from the processor.

The inclusion of one or more flexible communication cable(s) having oneor both ends be adapted for selective interconnection to anddisconnection from other system componentry facilitates replacement,servicing, and upgrading of system componentry, as well as migration ofa patient from one type of auditory stimulation device to another (e.g.migration from a middle ear stimulation device to a cochlear stimulationdevice).

One cable end connector design that may be utilized is described in U.S.Pat. No. 6,517,476, hereby incorporated by reference in its entirety.Another cable end connector design and implantable connector that may beutilized is described in U.S. patent application Ser. No. 12/016,765,hereby incorporated by reference in its entirety.

In one approach, a processor may be located within an implantable firsthousing together with a first microphone. The processor may compriseanalog and/or digital logic componentry for conditioning first andsecond microphone output signals separately and/or as combined. Forexample, analog filters may be employed to attenuate or shape thefrequency response of the microphones. Analog circuits may also beapplied to cancel signals. Digital signal processing via FIR or IIRfilters may be applied for similar purpses. Additionally, frequencydomain processing via FFT may be applied for frequency shaping or noisecancellation. In certain embodiments, signal noise cancellation may befacilitated via the inclusion of one or more motion sensor(s) (e.g.accelerometer(s)) disposed in one or more implantable housing(s)together with one or more microphones. In this regard, signal processingfunctionality may be included as taught by U.S. Patent ApplicationPublication Nos. 2007/0167671, 2005/0101831, 2006/0155346, 2008/0132750and U.S. Pat. No. 7,214,179, each of which is hereby incorporated byreference in its entirety. As noted above, the processor may alsoinclude a processing module beamforming and/or directionality purposes.

Additionally, in certain embodiments a power storage device (e.g. arechargeable battery) and other componentry may be disposed within thefirst housing. Further, a receiver adapted to receive transcutaneouswireless signals may be interconnected to the first housing. In oneapproach, a receiver (e.g. an inductive coil) may be encapsulated by abiocompatible capsule that is interconnected to the first housing.Additional system componentry may be implemented, e.g. as disclosed inU.S. Patent Application Publication No. 200610183965, herebyincorporated by reference in its entirety.

An improved method for use with an implantable auditory stimulationsystem device is also provided. The method includes the step ofpositioning at least a first microphone at a first subcutaneouslocation, wherein the first microphone is operative to transcutaneouslyreceive acoustic signals and generate a first microphone output signalin response thereto. The method additionally includes the step oflocating at least a second microphone at a second subcutaneous locationof the patient, wherein the second microphone is operative totranscutaneously receive acoustic signals and generate a secondmicrophone output signal in response thereto. The method furtherprovides for operatively interconnecting a processor to the firstmicrophone and to the second microphone, wherein the processor isoperative to combinatively use the first microphone output signal andthe second microphone output signal to generate a drive signal to drivethe implantable auditory stimulation device.

In one approach, at least a first microphone may be fixedly disposedwithin a first housing and at least a second microphone may be fixedlydisposed within a separate second housing, wherein the first and secondhousings may be separately positioned at offset subcutaneous locations.In another approach, at least two microphones may be disposed at offsetlocations within a common housing.

In another aspect, two or more microphones may be offset with at least apredetermined spacing therebetween to facilitate combinative use of themicrophone output signals by a processor for beamforming ordirectionality purposes. That is, offset microphones may be disposed andtheir output signals processed to simulate natural hearing, e.g. so thatacoustic signals received by a patient from a forward direction areperceived more prominently than acoustic signals received by a patientfrom a rearward direction.

In one aspect, the positioning of a first microphone may entail locatinga corresponding first housing in spaced relation to a surface of a skullof the patient, wherein the first microphone is at least partiallyisolated from skull borne vibrations by soft tissue disposed between thefirst microphone and the skull of a patient. In a related aspect,positioning of a second microphone may provide for mounting acorresponding second housing to the skull of a patient.

In yet another aspect, the method may further includes the steps ofsensing acoustic signals at a first microphone with a firstpredetermined minimum sensitivity across a first frequency range, andsensing acoustic signals at a second microphone with a secondpredetermined minimum sensitivity across a second frequency range,wherein the first and second microphone output signals are provided. Thefirst and second frequency ranges may be at least partially overlapping.

In the various embodiments, the processor may combinatively process themultiple microphone signals and generate an appropriate drive signal. Inturn, an auditory stimulation device may utilize the drive signal tostimulate a component of a patient's auditory system.

Additional features and advantages will become apparent to those skilledin the art upon consideration of the further description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an embodiment of an implantable auditory stimulationsystem for middle ear stimulation.

FIG. 2 illustrates the embodiment of FIG. 1 in an implanted arrangement.

FIG. 3 illustrates an embodiment of an implantable auditory stimulationsystem for cochlear stimulation.

FIG. 4 illustrates the embodiment of FIG. 3 in an implanted arrangement.

FIGS. 5, 6, 7 and 6 schematically illustrate additional embodiments ofimplantable auditory stimulation systems.

DETAILED DESCRIPTION

FIGS. 1 and 2 illustrate one embodiment of an implantable auditorystimulation system 1. The system 1 may include a first housing 20 thathouses a first microphone 30 for transcutaneous receipt of acousticsignals. In one approach, the first microphone 30 may include adiaphragm 32 disposed at a skin-facing side of the first housing 20. Thefirst housing 20 may further house a processor 40 for processing anaudio output signal from the first microphone 30, as well as additionalcomponentry noted hereinbelow.

The system 1 may also include a second microphone 60 located in a secondhousing 66. In one approach, the first microphone 60 may include adiaphragm 64 disposed at a skin-facing side of the second housing 66.The second microphone 60 may be operatively interconnected with theprocessor 40, wherein the processor 40 may process an audio outputsignal from the second microphone 60. In this regard, the processor 40may utilize audio output signals from both the first microphone 30 andsecond microphone 60 to generate a drive signal.

In turn, the system may include an auditory stimulation device 50 a forstimulating a patient's auditory system in response to the drive signal.In the illustrated embodiment, the auditory stimulation device 50 a isfor middle ear stimulation, e.g. an electromechanical transducer.

Electrical interconnections between the second microphone 60 andauditory stimulation device 50 and signal processor 40 may be realizedvia the inclusion of a connector 70 that may be electricallyinterconnected with signal processor 40 via a flexible communicationcable 72. As shown, the communication cable 72 may be fixedlyinterconnected at one end to the implantable housing 20 and processor 40housed therein, and to the connector 70 at the other end. Alternatively,one or both ends of the communications cable 72 may be provided to beselectively interconnectable to and disconnectable the implantablehousing 20 and/or connector 70.

As shown in FIG. 1, the second microphone 60 and auditory stimulationdevice 50 may be electrically interconnected to connector 70 viacorresponding flexible communication cables 62 and 52, respectively. Thecommunication cables 62 and 52 may be fixedly interconnected orselectively interconnectable/disconnectable to connector 70 at firstconnector ends 68 and 58, respectively. In this regard, and as shown inFIG. 1, connector 70 may be provided with advanceable/retractablelocking members 74 a, 74 b for selective, secure interconnection ofconnector 70 to a connector end 58 of communication cable 52 that may beinserted into an interface aperture of connector 70. Further, connection70 may be provided with locking members 76 a, 76 b for selective secureinterconnection of connection 70 to a connector end 68 of communicationcable 62 that may be inserted into an interface aperture connection 70.

Additionally, a second end of communication cable 52 may be fixedlyinterconnected to auditory stimulative device 50, as shown in FIG. 1, orselectively interconnectable to and disconnectable from auditorystimulation device 50. Similarly, a second end of communication cable 62may be fixedly interconnected to second microphone 60, as shown, orselectively interconnectable to and disconnectable from secondmicrophone 60.

The optional interconnectability/disconnectability features noted abovemay be employed to facilitate the ability to service, upgrade, and/orreplace componentry, or to migrate from one type of auditory stimulationdevice 50 to another, without removal of other implant systemcomponentry. In turn, medical personnel efficiencies and enhancedpatient care may be realized.

In some implementations, an implantable capsule 10 may be provided thatcarries an antenna 90 (e.g. an inductive coil) adapted to receive and/ortransmit transcutaneous wireless signals from an external antenna, aswell as a magnet 92 that functions with an external magnet to maintainpositioning of an external wireless signal transmitter and/or receiver.In this regard, the capsule 10 may encapsulate the antenna 90, magnet92, housing 20 and electrical interconnections between antenna 90 andhousing 20. For purposes of illustration, a portion of capsule 10 iscut-away in FIG. 1 to show the housing 20. The inclusion of capsule 10facilitates interconnected positioning of housing 20 and antenna 90during implant procedures. In one approach, capsule 10 may comprise anover-molded, silicon-based material.

By way of example, the antenna 90 may be provided to receivetranscutaneous signals that comprise radio frequency (RF) power signals.In turn, the RF power signals may be utilized for powering the variousimplanted componentry. In one approach, the housing 20 may furtherinclude a power storage device 80 (e.g. a rechargeable battery), whereinthe RF power signals are received and converted to an electrical signalby antenna 90, and then utilized to recharge the power storage device80.

In certain arrangements, the transcutaneous signals may comprise RFaudio signals. By way of example, such RE audio signals may compriseaudio signals generated by external devices such as audio equipment,telephones (e.g. cellular telephones), assistive listening devices,external microphones and/or external headsets (e.g. Bluetooth headsets).In turn, the RF audio signals may be utilized by processor 40 to providea drive signal to the auditory stimulation device 50 a.

Reference is now made to FIG. 2 which illustrates the system 1 of FIG. 1in an implanted state. As shown, the housing 20 may be located at afirst location on the skull of a patient. Such skull placement providesfor stable positioning of the first microphone 20, thereby yielding astable transfer function between acoustic signals received at the firstmicrophone 30 and the audio output signal generated in response thereto.Further, placement of first microphone 30 at the skull interfacelocation illustrated in FIG. 2 offers the advantage of a relativelyconstant and thin skin thickness overlying the diaphragm of the firstmicrophone 30, thereby enhancing the transfer function, as well asreducing the low frequency content of the microphone output signal dueto body noise as compared to microphones placed in soft tissue.Microphones placed in soft tissue are typically subject to largeamplitude low frequency signals due to both the patient's own voice aswell as due to gross movements of the muscles of the neck.

The positioning of the second microphone 60 on soft tissue of a patient,e.g. in the neck region illustrated in FIG. 2, yields the advantage ofisolating the second microphone 60 from skull-borne vibrations. In thisregard, skull-borne vibrations may result from operation of an auditorystimulation device 50 a. Skull-borne vibration may also arise naturallyfrom a patient's own voice, chewing or coughing. In each of the notedcases, vibrations may be transmitted to the site of an implantedmicrophone, received by a microphone diaphragm, and then amplified,thereby introducing undesired noise into the system. Positioning ofsecond microphone 60 on soft tissue of a patient reduces such noise inthe audio output signal of second microphone 60.

As shown in FIG. 2 the auditory stimulation device 50 a may besupportably connected to a positioning system 100, which in turn, may beconnected to a bone anchor 110 mounted within a patient's mastoidprocess (e.g. via a hole drilled into the cortical surface of theskull). In the illustrated embodiment, auditory stimulation device 50 amay comprise an actuator 56 a for contact interface with the ossicularchain OC of the patient. As shown, the actuator 56 a may provide formechanical stimulation of the ossicular chain, e.g. through thetransmission of vibrations to the incus of the patient's ossicularchain.

The processor 60 may comprise circuitry and other analog componentryand/or digital componentry for processing the audio output signals fromthe first microphone 30 and from the second implanted microphone 60.Such componentry may provide for frequency shaping, amplification,weighting, compression and other signal conditioning steps, includingconditioning based on patient-specific fitting parameters. One or moreof such conditioning steps may be provided separately in relation to theaudio output signals from the first microphone 30 and from the secondmicrophone 60. Additionally and/or alternatively, one or more suchsignals conditioning steps may be carried out during or after processor60 has combined the audio output signals from first microphone 30 andsecond microphone 60. For example, circuits and/or signal processingalgorithms may cancel electrical noise, unwanted signals such as bodygenerated noise or the patient's own voice, or signal processingartifacts. Additionally, algorithms for beamforming or directionalitymay be employed.

In relation to the first microphone 30 and second microphone 60, suchmicrophones may be advantageously designed to yield differentsensitivity characteristics in relation to the corresponding intendedplacement of such microphones. By way of example, in one embodiment thefirst microphone 30 may be provided to have a sensitivity of at leastapproximately −60 to −50 dB V/0.1 Pa across a frequency range of about50 H_(z) to 3000 Hz. Second microphone 60 may be designed to have aminimum sensitivity of approximately −60 to −50 dB V/0.1 Pa across afrequency over an acoustic frequency range of between about 1500 H_(z)to 10000 H_(z). By virtue of such offset sensitivity characteristics theoutput signals from the first microphone 30 and second microphone 60 maybe combinatively processed to yield an enhanced drive signal for drivingthe auditory stimulation device 50 a.

Reference is now made to FIGS. 3 and 4 which illustrates one embodimentof an implantable auditory stimulation system 2 that includes anauditory stimulation device 50 b in the form of a cochlear implantstimulation device. In this regard, the cochlear implant stimulationdevice 50 b shown in FIG. 3 may include an electrode array 51 a forinsertion into a patient's cochlea, a reference electrode 53 a (e.g. forinterconnection to a patient's skull typically near the temporalismuscle), and an optional module 55 a for wireless interface withexternal componentry and/or for signal processing additional to thatcompleted by processor 40. In the later regard, wireless input may besupplied to module 55 b from external audio sources such as personalaudio devices, microphones, or external speech processors. Othercomponents of the system 2 may be the same as described above inrelation to system one of FIGS. 1 and 2.

Reference is now made to FIGS. 5-8 which schematically illustrateadditional embodiments of implantable auditory stimulation systems. InFIG. 5 an implantable auditory stimulation system 3 includes an implanthousing 200 that may house at least a first microphone 300, a processor400 and other componentry (e.g. power storage device 800). The implanthousing 200 may be structurally interconnected to a antenna 900 (e.g. anindicative coil) for receiving and/or transmitting wirelesstranscutaneous signals.

At least a second implantable microphone 600 (e.g. located in a separateimplant housing) may be operatively interconnected or interconnectableto the processor 403 at implant housing 200. Output signals from thefirst microphone 300 and the second microphone 600 may be combinativelyprocessed by the processor 400 to generate a drive signal.

In this regard, a stimulation device 500 may be interconnected orinterconnectable to a connector 700 which may be interconnected orinterconnectable to the processor 400 at implant housing 200. In turn,the drive signal generated by the processor 400 may be provided to thestimulation device 500. The stimulation device 500 may comprise a middleear stimulation device and/or a neurostimulation device (e.g. a CIstimulation device or an ABI stimulation device).

FIG. 6 illustrates an implantable auditory stimulation system 4 thatincludes an implant housing 201 that may house a processor 401 and othercomponentry (e.g. a power storage device 801). The implant housing 201may be structurally interconnected to an antenna 901 for receivingand/or transmitting wireless transcutaneous signals.

At least a first implantable microphone 301 and second implantablemicrophone 601 may be interconnected or interconnectable to theprocessor 401 at implant housing 201 via a connector 701 that may beinterconnected or interconnectable to the processor 401 at implanthousing 201. In turn, output signals from the first microphone 301 andthe second microphone 601 may be combinatively processed by theprocessor 401 to generate a drive signal. As illustrated, additionalmicrophones may be optionally interconnected via connector 701 to theprocessor 401 at implant housing 201, wherein output signals from suchadditional microphones may be combinatively employed with the outputsignals of the first implantable microphone 301 and second implantablemicrophone 601.

A stimulation device 501 may be interconnected or interconnectable viathe connector 701 to the processor 401 at implant housing 201. In turn,the drive signal generated by the processor 401 may be provided to thestimulation device 501. The stimulation device 501 may comprise a middleear stimulation device and/or neurostimulation device (e.g. a CIstimulation device or an ABI stimulation device).

FIG. 7 illustrates a further implantable auditory stimulation system 5that includes an implant housing 202 that may house a processor 402 andother componentry (e.g. a power storage device 802). Additionally, theimplant housing 202 may house at least a first microphone 302 and asecond microphone 602 at spatially offset locations. The output signalsfrom the first microphone 302 and second microphone 602 may becombinatively processed by the processor 402 to generate a drive signal.As shown, additional microphones may also be disposed within implanthousing 202.

In the illustrated arrangement, the implant housing 202 may bestructurally interconnected to an antenna 902 for receiving and/ortransmitting wireless transcutaneous signals. Such structuralinterconnection may be provided via an over-molded capsule (e.g.comprising a silicon-based material).

A stimulation device 502 may be interconnected or interconnectable via aconnector 702 to the processor 402 at implant housing 202. In turn, thedrive signal generated by the processor 402 may be provided to thestimulation device 502. The stimulation device 502 may comprise a middleear neurostimulation device (e.g. a CI stimulation device or an ABIstimulation device).

FIG. 8 illustrates yet another implantable auditory stimulation system6. The implantable auditory stimulation system 6 may include an implanthousing 203 that houses at least a first microphone 303, a processor 403and other componentry (e.g. a power storage device 803). The implanthousing 203 may be structurally interconnected to an antenna 903 (e.g.an inductive coil) for receiving and/or transmitting wirelesstranscutaneous signals.

At least a second implantable microphone 603 a (e.g. located in aseparate implant housing) and a third implantable microphone 603 b (e.g.located in a separate implant housing) may be operatively interconnectedor interconnectable via a connector 703 to the processor 403 at implanthousing 230. Output signals from the first microphone 303, secondmicrophone 603 a and third microphone 603 b may be combinativelyprocessed by the processor 403 to generate a drive signal.

In this regard, a stimulation device 503 may be interconnected orinterconnectable to the connector 703. In turn, the drive signalgenerated by a processor 403 may be provided to the stimulation device503. The stimulation device may comprise a middle ear stimulation deviceand/or neurostimulation device (e.g. a CI stimulation device or an ABIstimulation device).

Additional embodiments, implementations and additions to those describedabove will be apparent to those skilled in the art and are intended tobe within the scope of the present invention.

1-20. (canceled)
 21. An implantable auditory stimulation system,comprising: a plurality of microphones, including at least a firstmicrophone, operative to transcutaneously receive acoustic signals andgenerate a first microphone output signal in response thereto, and asecond microphone operative to receive acoustic signals and generate asecond output signal in response thereto; a processor, operativelyinterconnected to said first microphone and to said second microphone,configured to use said first microphone output signal and said secondmicrophone output signal to generate a signal; and an implantableauditory stimulation device, operatively interconnected to saidprocessor, adapted to stimulate an auditory system of a patient inresponse to said generated signal, wherein the implantable auditorystimulation device includes at least one of an electrode apparatusconfigured to apply electrical current to tissue of the recipient or anactuator configured to provide mechanical stimulation to tissue of therecipient.
 22. The implantable auditory stimulation system of claim 21,wherein: the implantable auditory stimulation device includes theactuator; and the actuator is an actuator configured for middle earstimulation.
 23. The implantable auditory stimulation system of claim21, wherein: the implantable auditory stimulation device includes theelectrode apparatus configured to apply electrical current to tissue ofthe recipient.
 24. The implantable auditory stimulation system of claim21, wherein: the implantable auditory stimulation device includes theelectrode apparatus configured to apply electrical current to tissue ofthe recipient; and the electrode apparatus configured to applyelectrical current to tissue of the recipient includes an electrodearray configured for insertion into a patient's cochlea.
 25. Animplantable auditory stimulation system as recited in claim 21, whereinsaid first microphone has a first predetermined minimum sensitivityacross a first predetermined frequency range, wherein said secondmicrophone has a second predetermined minimum sensitivity across asecond frequency range, and wherein said first and second predeterminedfrequency ranges are at least partially non-overlapping.
 26. Theimplantable auditory stimulation system of claim 21, wherein: theimplantable auditory stimulation device is part of a temporal boneconduction hearing system.
 27. An implantable auditory stimulationsystem as recited in claim 21, wherein: the plurality of microphonesincludes at least a third microphone that is an external microphoneoperative to receive acoustic signals directly from air and generate athird output signal in response thereto, and the second microphone isoperative to transcutaneously receive the acoustic signals and generatethe second output signal in response thereto.
 28. An implantableauditory stimulation system as recited in claim 21, wherein: the secondmicrophone is an external microphone.
 29. A method for use with animplantable auditory stimulation system device, comprising: positioninga first microphone at a first implanted location of a patient, whereinsaid first microphone is operative to transcutaneously receive acousticsignal and generate a first microphone output signals in responsethereto; positioning a second microphone at a second implanted locationof said patient, offset from said first implanted location, wherein saidsecond microphone is operative to transcutaneously receive acousticsignals and generate a second microphone output signal in responsethereto; and operatively interconnecting a processor to said firstmicrophone and to said second microphone, wherein said processor isoperative to use said first microphone output signal and said secondmicrophone output signal to generate a drive signal to drive animplantable auditory stimulation device.
 30. A method as recited inclaim 29, wherein said positioning step comprises: locating said firstmicrophone at in spaced relation to a surface of a skull of the patient,wherein said first microphone is at least partially isolated from bonevibrations due to the spaced relationship to the surface of the skull.31. A method as recited in claim 30, wherein said first microphone isdisposed in a first housing and said second microphone is disposed in asecond housing, and wherein said operatively connecting step comprises:selectively interconnecting said processor to at least one of said firstmicrophone and second microphone utilizing a flexible communicationcable.
 32. A method as recited in claim 30, wherein said firstmicrophone is disposed in a first housing and said second microphone isdisposed in the first housing, and wherein said operatively connectingstep comprises: selectively interconnecting said processor to at leastone of said first microphone and second microphone utilizing a flexiblecommunication cable.
 33. A method for use with an implanted auditorystimulation system device implanted in a recipient, comprising:receiving with an implanted processor a first signal based on firstoutput from a first microphone at a first implanted location of therecipient, wherein said first microphone is operative totranscutaneously receive acoustic signals and generate the first outputin response thereto; receiving with the implanted processor a secondsignal based on output from a second microphone offset from said firstimplanted location, wherein said second microphone is operative toreceive acoustic signals and generate the second output in responsethereto; and using said implanted processor to generate a drive signalto drive an implantable auditory stimulation device based on at leastone of the received first signal or second signal.
 34. The method ofclaim 33, wherein the action of using said implanted processor togenerate the drive signal to drive an implantable auditory stimulationdevice based on at least one of the received first signal or secondsignal includes using said implanted processor to generate the drivesignal to drive an implantable auditory stimulation device based on thereceived first signal and the second signal.
 35. The method of claim 33,wherein the second microphone is a microphone external to the recipient.36. The method of claim 33, wherein second microphone is a microphoneimplanted at a location offset from the first microphone.
 37. The methodof claim 33, wherein the second signal is a signal from an externalspeech processor.
 38. The method of claim 33, further comprising: usingthe first and second signal for beamforming and/or directionalitypurposes.
 39. The method of claim 33, wherein: the first microphone hasa body interfacing architecture that is different from any sucharchitecture of the second microphone.
 40. The method of claim 33,further comprising: using the first and second signals to enhance thedrive signal beyond that which would be the case if only one of thefirst and second signals was available.
 41. The method of claim 33,further comprising: executing combinative processing of the first andsecond signals to ultimately improve the drive signal.
 42. The method ofclaim 33, further comprising: executing combinative processing of thefirst and second signals to enhance the drive signal, where the secondmicrophone is implanted in the recipient.
 43. The method of claim 33,further comprising: executing combinative processing of the first andsecond signals to generate the drive signal.
 44. The method of claim 33,further comprising: executing combinative processing of the first andsecond signals for at least one of beamforming or directionalitypurposes.
 45. The method of claim 33, wherein: the first microphone issubjected to a different amount of bone conducted vibrations than thesecond microphone, wherein the second microphone is implanted in therecipient.
 46. The method of claim 33, wherein: the first microphone atleast partially isolated from bone conducted vibrations by an amountmore than the second microphone.
 47. The method of claim 33, furthercomprising: receiving acoustic signals at said first microphone with afirst predetermined minimum sensitivity across a first frequency range,and at said second microphone with a second predetermined minimumsensitivity across a second frequency range, to provide said firstsignal and said second signal, respectively.
 48. The method of claim 33,wherein: the second microphone is an implanted microphone; and themethod further comprises: receiving with the implanted processor a thirdsignal based on third output from a third microphone external to therecipient, wherein said third microphone is operative to receiveacoustic signals and generate the third output; and using said implantedprocessor to generate a drive signal to drive an implantable auditorystimulation device based on the received third signal.
 49. The method ofclaim 33, wherein the action of using said implanted processor togenerate the drive signal is executed without noise cancellation.
 50. Amethod as recited in claim 33, further comprising: combining said firstand second signals to generate said drive signal.